1. Technical Field
The present invention relates in general to the field of computers, and, in particular, to portable laptop computers. Still more particularly, the present invention relates to an improved method and system for detecting when a laptop computer housing is positioned on a user""s lap, thus requiring adjustment to a heat management system of the computer to cool the bottom of the computer housing to prevent discomfort or injury to the user.
2. Description of the Related Art
Personal computers, including laptop computers, have acquired very high levels of computing power despite their relatively small size. Much of this computing power is due to the use of high density integrated circuit packages, including a central processing unit (CPU). These high density integrated circuit packages, and particularly the CPU, use a significant amount of electricity, which generates high levels of local heat within the laptop computer housing. For example, a typical CPU is rated to operate normally at temperatures up to 100xc2x0 C. (212xc2x0 F.) while generating over 50 watts of heat. This heat radiates throughout the computer housing, including the bottom surface of the computer housing. Under normal operating conditions, when placed on a desktop or other solid surface, the bottom of the computer housing does not get hot enough to pose a fire hazard or a serious health risk. However, despite the laptop computer""s name, even under normal operating conditions the bottom of the laptop computer can get hot enough to cause discomfort or, in extreme conditions, even injury to a user who operates the laptop computer on the user""s lap.
Thus, there is a need for a temperature control method and system for a laptop computer that is dependent on where the laptop computer is placed during operation, particularly with reference to placement of the laptop computer on the user""s lap.
The present invention provides a method and system for detecting when a laptop computer is placed on a lap of a user, thus indicating the need to keep the bottom of the laptop computer at a lower temperature to enhance the user""s desired comfort level. The temperature of the bottom of the laptop computer is controlled by adjusting the amount of heat that radiates from an interior of the laptop computer housing to the bottom of the laptop computer housing. When the laptop computer is placed on the lap of the user, or alternatively another surface that has direct contact with the bottom of the laptop computer housing, sensors on the bottom of the laptop computer housing are activated. The sensors provide a signal to the laptop computer to initiate supplemental cooling measures to reduce the temperature of the bottom of the laptop computer housing. Supplemental cooling measures taken may include decreasing an operating speed of logic circuits such as a central processing unit (CPU), or increasing a cooling fan output.
The above, as well as additional objectives, features, and advantages of the present invention will become apparent in the following detailed written description.